interior truss heel sheathing

[struct_eeyore]

I have a series of wood trusses terminating on the interior of the building which have some very tall heels (13'+)
There is no shear transfer by design here - although some might occur in reality.
I'm leaning towards sheathing this section full height, but am wondering if that might be overkill - in lieu of X-bracing.
(truss profile is hatched in figure below)

 

[KootK]

I do feel that is overkill if there is no explicitly need for shear transfer at the interior location. Sheathing that for sport may perceived as incurring meaningful expense needlessly. Unless I misunderstand the situation, all you need there is the end vertical bracing at the locations specified by the truss manufacturer.

 

[Flotsam7018]

I definitely get concerned with adequate rollover restraint and keeping the end vertical plumb in situations like this. So I don’t find it overkill, especially since I’ve seen a lot of truss bracing missed or not installed properly. I have specified truss panels between trusses at an interior bearing with tall heels like this like you’d do for a shear wall, sheathing is likely easier but if you’ve got trusses coming in from both sides the panels become the most practical option I have found.

 

[JAE]

If you don't need the sheathing to transfer lateral loads to a shear wall below - the only reason to do it would be temporary during construction.
Once all the roof sheathing is in place, the "whole" of the roof system would probably be quite stable - assuming a hip type roof perhaps.

 

[KootK]

I definitely get concerned with adequate rollover restraint and keeping the end vertical plumb in situations like this.

Similar to @JAE, I don't see a rollover demand here other than in the erection condition. I see the top chord of the truss being laterally restrained by the roof diaphragm and the bottom chord being laterally restrained by the supporting wall and / or ceiling diaphragm. Add those two together, and would think that you have very effective rollover restraint. That said, I have seen some situations where I've had so little confidence in the diaphragm detailing that have questioned the issue of rotational restraint.

 

[Flotsam7018]

Heck, I block floor joists at an interior bearing for rotational restraint, I’m definitely going to do that for an extremely slender truss web and not rely on the roof sheathing and toenails at the top plate. Any out of straightness/plumb or secondary effects of the web wouldn’t be addressed either.

Perhaps I’m jaded as I’ve seen an end web buckle about 2” along the weak axis in this exact scenario.

 

[KootK]

I’m definitely going to do that for an extremely slender truss web

I believe that you are speaking to a K=1-sh buckling of the truss web rather than a wholesale rollover of the truss. Those are different things in my mind. The former can be addressed by as little as a line or two of horizontal strapping that hits an x-brace once in a while. Similar to OWSJ bottom chord bracing.

Heck, I block floor joists at an interior bearing for rotational restraint

I see your point to an extent. However, I would argue that:

1) There are several reasons for such blocking of which rotational restraint is only one.

2) I doubt that rotational restraint is required in the complete system in many cases. Certainly, I've seen a whole lot of 2x10 lapped bearing conditions without blocking that have preformed just fine.

3) Such rotation restraint is deemed worthwhile because the joists are so shallow. On a typical roof truss end, you're lever arm between the diaphragm and wall lateral restraints is going to be functionally enormous.